Small Crosses #115
 Stripes  CC BY-SA 3.0

Sharp pixel pattern looking like some sort of fabric.

Source Dmitry

 More Textures
Pinstripe #35
 Light  CC BY-SA 3.0

Light gray pattern with a thin pinstripe.

Source Brandon

Sports car pattern 2 #2441
 Colorful  CC 0

A seamless pattern formed from a sports car on clker.com. To get the tile, select the rectangle in Inkscape and use shift+alt+i.

Source Firkin

Background pattern 230 (colour 2) #2302
 Green  CC 0

To get the tile this is based on, select the rectangle in Inkscape and use shift-alt-i.

Source Firkin

Groovepaper #577
 Paper  CC BY-SA 3.0

With a name like this, it has to be hot. Diagonal lines in light shades.

Source Isaac

Project Papper@2X #120
 Paper  CC BY-SA 3.0

Light square grid pattern, great for a “DIY projects” sort of website, maybe?

Source Rafael Almeida

Green Fibers #91
 Dark  CC BY-SA 3.0

The green fibers pattern will work very well in grayscale as well.

Source Matteo Di Capua

Polaroid@2X #188
 Wall  CC BY-SA 3.0

Smooth Polaroid pattern with a light blue tint.

Source Daniel Beaton

Sine wave background 2 #1734
 Dark  CC 0

The tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i

Source Firkin

Greek key pattern 5 #2294
 Dark  CC 0

Seamless pattern made from a tile that can be obtained in Inkscape by selecting the rectangle and using shift+alt+i.

Source Firkin

Prismatic Abstract Line Art Pattern Background@2X #566
 Dark  CC 0

Prismatic Abstract Line Art Pattern Background

Source GDJ

Prismatic Curved Diamond Pattern 4 No Background@2X #542
 Diamond  CC 0

Prismatic Curved Diamond Pattern 4 No Background

Source GDJ

Prismatic Abstract Geometric Background 4 No Black #441
 Dark  CC 0

Prismatic Abstract Geometric Background 4 No Black

Source GDJ

Handmade Paper@2X #38
 Paper  CC BY-SA 3.0

White handmade paper pattern with small bumps.

Source Marquis